Any further wisdom available?

Please provide a short self-contained program which replicates your problem. Then, provide all the debug output from that program even if it isn't helpful (please include Dumper output of both CGI and CGI::Session object). Also provide module version information (use Devel::Modlist).

This is the code for sub flush:

sub flush {
    my $self = shift;

    # Would it be better to die or err if something very basic is wron
+g here? 
    # I'm trying to address the DESTORY related warning
    # from: http://rt.cpan.org/Ticket/Display.html?id=17541
    # return unless defined $self;

    return unless $self->id;            # <-- empty session
    
    # neither new, nor deleted nor modified
    return if !defined($self->{_STATUS}) or $self->{_STATUS} == STATUS
+_UNSET;

    if ( $self->_test_status(STATUS_NEW) && $self->_test_status(STATUS
+_DELETED) ) {
        $self->{_DATA} = {};
        return $self->_unset_status(STATUS_NEW | STATUS_DELETED);
    }

    my $driver      = $self->_driver();
    my $serializer  = $self->_serializer();

    if ( $self->_test_status(STATUS_DELETED) ) {
        defined($driver->remove($self->id)) or
            return $self->set_error( "flush(): couldn't remove session
+ data: " . $driver->errstr );
        $self->{_DATA} = {};                        # <-- removing all
+ the data, making sure
                                                    # it won't be acce
+ssible after flush()
        return $self->_unset_status(STATUS_DELETED);
    }

    if ( $self->_test_status(STATUS_NEW | STATUS_MODIFIED) ) {
        my $datastr = $serializer->freeze( $self->dataref );
        unless ( defined $datastr ) {
            return $self->set_error( "flush(): couldn't freeze data: "
+ . $serializer->errstr );
        }
        defined( $driver->store($self->id, $datastr) ) or
            return $self->set_error( "flush(): couldn't store datastr:
+ " . $driver->errstr);
        $self->_unset_status(STATUS_NEW | STATUS_MODIFIED);
    }
    return 1;
}
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If all else fails you can copy it into your program and add debug statements

sub CGI::Session::flush {
package CGI::Session;
...
   warn "so far so good";
...
}
[download]